From 6945342a1f0a4caaa918f2b0b1efef88824439e0 Mon Sep 17 00:00:00 2001 From: Eric Wong Date: Fri, 5 Jun 2009 18:03:46 -0700 Subject: Transfer-Encoding: chunked streaming input support This adds support for handling POST/PUT request bodies sent with chunked transfer encodings ("Transfer-Encoding: chunked"). Attention has been paid to ensure that a client cannot OOM us by sending an extremely large chunk. This implementation is pure Ruby as the Ragel-based implementation in rfuzz didn't offer a streaming interface. It should be reasonably close to RFC-compliant but please test it in an attempt to break it. The more interesting part is the ability to stream data to the hosted Rack application as it is being transferred to the server. This can be done regardless if the input is chunked or not, enabling the streaming of POST/PUT bodies can allow the hosted Rack application to process input as it receives it. See examples/echo.ru for an example echo server over HTTP. Enabling streaming also allows Rack applications to support upload progress monitoring previously supported by Mongrel handlers. Since Rack specifies that the input needs to be rewindable, this input is written to a temporary file (a la tee(1)) as it is streamed to the application the first time. Subsequent rewinded reads will read from the temporary file instead of the socket. Streaming input to the application is disabled by default since applications may not necessarily read the entire input body before returning. Since this is a completely new feature we've never seen in any Ruby HTTP application server before, we're taking the safe route by leaving it disabled by default. Enabling this can only be done globally by changing the Unicorn HttpRequest::DEFAULTS hash: Unicorn::HttpRequest::DEFAULTS["unicorn.stream_input"] = true Similarly, a Rack application can check if streaming input is enabled by checking the value of the "unicorn.stream_input" key in the environment hashed passed to it. All of this code has only been lightly tested and test coverage is lacking at the moment. [1] - http://tools.ietf.org/html/rfc2616#section-3.6.1 --- examples/echo.ru | 32 ++++++++++++++++++++++++++++++++ 1 file changed, 32 insertions(+) create mode 100644 examples/echo.ru (limited to 'examples') diff --git a/examples/echo.ru b/examples/echo.ru new file mode 100644 index 0000000..e13721a --- /dev/null +++ b/examples/echo.ru @@ -0,0 +1,32 @@ +#\-E none +# Example application that echoes read data back to the HTTP client. +# This emulates the old echo protocol people used to run. +# +# An example of using this in a client would be to run: +# curl -NT- http://host:port/ +# +# Then type random stuff in your terminal to watch it get echoed back! + +Unicorn::HttpRequest::DEFAULTS["unicorn.stream_input"] = true +class EchoBody + def initialize(input) + @input = input + end + + def each(&block) + while buf = @input.read(4096) + yield buf + end + self + end + + def close + @input = nil + end +end + +use Rack::Chunked +run lambda { |env| + [ 200, { 'Content-Type' => 'application/octet-stream' }, + EchoBody.new(env['rack.input']) ] +} -- cgit v1.2.3-24-ge0c7